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    <script>
        var arr = [24, 34, 21, 9, 8];

        for (var i = 0; i < arr.length; i++) {
            var temp = arr[i];
            // for (var j = i - 1; j >= -1; j--) {
            //     if (temp < arr[j]) {
            //         arr[j + 1] = arr[j];
            //     } else {
            //         arr[j + 1] = temp;
            //         break;
            //     }
            // }
            var j = i - 1;
            while (temp < arr[j] && j >= 0) {
                arr[j + 1] = arr[j];
                j--;
            }
            arr[j + 1] = temp;
        }
        console.log(arr);
    </script>
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